Improvement in molds for artificial teeth



UNITED. STATES PATENT OTTueE.

J OHN. A. MOOLELLAND, OF LOUISVILLE, KENTUCKY.

VlMPRovl-:ivlEmiIN MoLDs FOR ARTI-FICIAL TEETH.

Speciiiation forming Vpart of` `Letters Patent No. 76,221, dated March31, 1868.

To all whom it may concern:

Be it known that I,JoHN A. MCGLELLAND, of Louisville, in the countyOf-Jeierso'n and State of Kentucky, 'have invented'newand Improved Moldsfor Forming Dental Blattes, 85e.; and I do hereby declare that thefollowing is afull, clear, and exact description thereof, which willenable those skilled in the art to make and use the same, referencebeing had to the accompanying drawings, forming part of thisspecification.

Figure l represents the first operation for building the mold for adental plate, showing a central vertical section of the cylinder-flask,containing a plaster impression of the gums, on which is cast ametalform as a base for the mold. Fig. 2 represents the metal form of theimpression thus taken, on which is built a form of plaster for thedental plate, with the teeth arranged in place. Fig. 3 represents theneXt operation in building the mold, showing the plaster plate on thebase within the lask, and the casting of a front section of the mold.Fig. 4 represents the next operation, showing the castings of the othersections of the mold. Fig. 5 represents the mold when completed, havingone side section removed. Fig. 6 represents thedetached side sectionremoved from Fig. 5. Fig. 7 represents the last operation in forming thedental plate in the mold.

Similar letters of reference indicate correspondin g parts.

This invention relates to a new and useful improvement in dental-platemolds; and consists in a metal mold constructed in sections within ametal ask, in such a manner that a dental plate may be molded and formedof rubber or other suitable plastic material by compression, ashereinafter described.

The first requisite in the construction of my improved section al metalmold is a clamp-Hash, A, made of brass, copper, or other suitable metal.The iiask is made with one side open, and fianges b b united and heldtogether by set-screws a., in such manner that the sides of the flaskshall bind tight upon the mold to keep the sections in place, whenconstructed within the iiask, and to bear a strong pressure for formingthe dental plate.

To build up a mold, the flask A is closed by the set-screws a, andplaced on a plane sur face on one end, and in the bottom of it isintroduced an impression, B, of the gums, takenv inthe usual way, inplaster or other suitableY substance that is refractory when set orcold.l

The impression B being thus provided and placed within the cylindricaltia-sk A, as shown inFig. 1, ametal mold,'c, is cast upon theimpression, which serves -as the base or founda tion of the mold for thedental'plate in subsequent o'perations. The foundation metal mold c isthen taken out of the flask, and, as shown in Fig. 2, a plaster form, D,is built upen it, with the teeth set in their respective places.

The mold O, with the plaster form D upon it, is then placed within theflask A, as shown in Fig. 3. The front section E of the mold is thencast by laying pads c c, of putty, clay, or other suitable material, onthe opposite sides of the form D, leaving a space between them forreceiving the metal section E, that is to be cast therein. A pad orcovering of putty is also placed, at the same time, behind the teeth, onthe face of the plaster form D, to protect the teeth, and coniine thesection E to the front side of the form.

In the next stage of the operation, the two side sections F F,Fig. 4,are formed by casting metal in the spaces left after removing the sidepads c c, as shown in Fig. 3. A center core, Gr, may also be cast at thesame time, or separately, on the top of the plaster form D. For thispurpose a strip or narrow pad of putty, d d, must be laid over thecutting-edges of the teeth, as shown in Fig. 4.

When these several parts of the mold have been cast as desired, and thepad d dhas been removed, a cap-piece, H, is then cast, which entersthespace made by removing the pad el d, and lls in between the cavities andinterstices of the teeth, forming a complete mold of thegrinding-surfaces and cuttingedges thereof, as shown in Fig. 5. Themetal mold, having been thus completely formed in sections, may be takenapart and set together again within the iiask A by loosening thesetsorews a. The plaster form D is removed and broken up, and the teethare set aside in their order, for subsequent formation of the dentalplate. rEhe mold is cleaned by picking all adherin g particles ofplaster out of the cavities, and the sections are then replaced inreverse position within the flask, in order to form and mold the dentalplate.

The flask A being` inverted on a plane surface, the cap-piece H isplaced withinit at the bottom. The front section E,the side sections FF, and the core Gare also all placed in proper relations, as shown inFig. 7. The teeth are then placed in their respective cavities .in theArnold, with their cutting-edges downward,

and around them and over the core G is packed the rubber or otherplastic material for forming the dental plate, as shown in Fig. 7. Theflask A is then screwed up tight, and the mold C is introduced on thetop, in reverse position from that which it occupied before. Ascrew-press is then applied to bear uponthe mold C, and press it downinto the flask upon the plastic material within the mold, by which,under powerful compression, every part of the mold is lled, and thedental plate is perfectly formed and molded.

It will be seen that at the junction of the anges b b there is acreviceor channel, which receives the metal when cast, and forms a sharpprojection on one side of the mold, that serves as a gage in replacingthe sections Within the flask.

'The mold and the dental platethus formed are held in place in the ilaskby means of a stirrup-clamp, bearing on the top and bottom pieces, insubsequent baking or hardening processes, to which the plate may besubjected.

A mold may thus be formed in sections of cast metal, for molding andforming plastic substances into any desired shape.

Having thus described my invention, I claim as new and desire to secureby Letters Patent- 1. A dental-plate mold formed in sections within ametal ask, substantially as described.

2. A metal clamp-flask, A,for said sectional dental-plate mold,constructed and operating substantially as herein described.

3. The method of forming a dental plate of plastic material within thesaid sectional mold, substantially as herein described. 1

WM. F. MCNAMARQ' ALEX. F. RoBERrs.

